On election night last year, there was an article published by the NY Times titled
Don't be Fooled by Virginia which explained how the (unique) nature of Virginia reporting its results will inevitably result in the Republican candidate taking an early lead, only to be overtaken by the Democratic candidate near the end.
Nonetheless, if this trend persists, I would still avoid calling Virginia for the Democratic candidate until such time the Democratic candidate actually overtakes the Republican candidiate.
